Improved Primitive support and better testing

This changeset addresses several issues.

- Improve primitive support so the status and output of an executed
primitive can be retrieved
- Merge latest upstream libjuju (required for new primive features)
- New testing framework
    This is the start of a new testing framework with the ability to
create and configure LXD containers with SSH, to use while testing proxy
charms.
- Add support for using ssh keys with proxy charms
    See Feature 1429. This uses the per-proxy charm/unit ssh keypair

Signed-off-by: Adam Israel <adam.israel@canonical.com>
diff --git a/modules/libjuju/juju/application.py b/modules/libjuju/juju/application.py
index 555bb3d..84afebe 100644
--- a/modules/libjuju/juju/application.py
+++ b/modules/libjuju/juju/application.py
@@ -228,13 +228,24 @@
         result = (await app_facade.Get(self.name)).constraints
         return vars(result) if result else result
 
-    def get_actions(self, schema=False):
+    async def get_actions(self, schema=False):
         """Get actions defined for this application.
 
         :param bool schema: Return the full action schema
-
+        :return dict: The charms actions, empty dict if none are defined.
         """
-        raise NotImplementedError()
+        actions = {}
+        entity = [{"tag": self.tag}]
+        action_facade = client.ActionFacade.from_connection(self.connection)
+        results = (
+            await action_facade.ApplicationsCharmsActions(entity)).results
+        for result in results:
+            if result.application_tag == self.tag and result.actions:
+                actions = result.actions
+                break
+        if not schema:
+            actions = {k: v['description'] for k, v in actions.items()}
+        return actions
 
     def get_resources(self, details=False):
         """Return resources for this application.
@@ -284,12 +295,10 @@
         )
         return await self.ann_facade.Set([ann])
 
-    async def set_config(self, config, to_default=False):
+    async def set_config(self, config):
         """Set configuration options for this application.
 
         :param config: Dict of configuration to set
-        :param bool to_default: Set application options to default values
-
         """
         app_facade = client.ApplicationFacade.from_connection(self.connection)
 
@@ -298,6 +307,19 @@
 
         return await app_facade.Set(self.name, config)
 
+    async def reset_config(self, to_default):
+        """
+        Restore application config to default values.
+
+        :param list to_default: A list of config options to be reset to their default value.
+        """
+        app_facade = client.ApplicationFacade.from_connection(self.connection)
+
+        log.debug(
+            'Restoring default config for %s: %s', self.name, to_default)
+
+        return await app_facade.Unset(self.name, to_default)
+
     async def set_constraints(self, constraints):
         """Set machine constraints for this application.